To: File

From: Jon Hagen

Date: April 10, 2003, 4-16-03

Subject: Alfa backend requirements - summarized by Avinash Deshpande in a conversation following an Alfa meeting today:

BW	Channels	Input	Output	Dump	Misc

levels	levels	time

1. P-Alfa	300MHz	1k	8 bits	4bits max	64usec	output after long-term

300kHz res.	min	(flexible)	mean removed in SW

2. E-Alfa	200MHz min	25kHz res	8bit min	16 bits	min	1sec	flexible blanking

(extragalactic)	(8000ch)	12 desired	@1 sec dumps	.1 (or even 1ms)	in hardware

for rfi excision

3. G-alfa HI	1415-1425	1kHz res min	10 desired	10 bits	1sec	blanking not

(galacatic HI:	=10k Channels	(few ok if little rfi)	needed*

(20k desired)

4. G-alfa	One 6MHz band	0.5 kHz	8 bits (min)	10bits	<1 sec.	blanking not

spec. line	+eleven	(1kHz min	needed*

3MHz bands	~ 40k channels)

(all fixed)

5. G- alfa	300MHz	1k	8 bits (min)	16 bits	0.1 sec	blanking not needed*

continuum

(like P-Alfa)

but w/full

Stokes

*rfi excised in software